A Half-Blood who was saved by Kimon no Kazu at some point prior to her arrival on OLYMPUS. One of the Oniwabanshu lead by Tatsumi Kisaragi, she is known to be the chi-specialist of the group. During the first night of the new semester, she participated in the Oniwabanshu's rescue of Firo Prochainezo and the three newly-arrived homunculi.
Demonic Ability: Kannazuki
Not a true Demonic Ability, but a Demonic Power born through the strength of the life-force flowing through Riko. As she releases her full potential, she becomes able to use the full extent of the chi-energy residing within her body, as her Demonic Power is purely dependant on that power. Without it, it could never actualize itself. Therefore, the aura it manifests is not that of a blood-thirsty beast, but that of Riko's own personality, of a gallant and just protector of the weak. However, the source from which the power spurs is, undoubtedly, a monster, and will always be so.
There are various ways to use this ability, but its most prominent power is to crush, disrupt, weaken or outright disintegrate prana. When Riko's attacks come in contact with spells or prana, they will be, depending on the nature and rank of the target, be either destroyed or weakened greatly. Magical constructs that are on par with normal humans are crushed almost without exceptions, and those of Servant level find themselves weakened. If the spells constructs are single-shot attacks or spells, they will immediately disintegrate or lose their power, but if they are continuous attacks of multiple rounds, they will be unable to act on certain number of those rounds.
Also allows the user to enhance her actions with pure chi-energy. Similar to the Servant Skill: Mana Burst.
Symphony Meem & Riko Ryuko
Crescent Judgment ~Howling, Noble Hunter~
Rank: C (S)
A physical attack that is combination of demonic power and magecraft. Bypassing the resistance of Riko via a route that is currently unknown, Symphony attaches ten time-variant spells into Riko, all separated by a single split of a second. For that instant, Riko and her attack exists in a single second ten times, and thus, delivers ten attacks at the prize of one. They culminate into a single, rapid-fire kick that deals extremely severe damage against anything magical or spiritual. Other information pending.